Hi Maria,
Thanks for sharing the file.
After checking your project, we see that the project is missing video and audio.
Did you rename the project file?
ActivePresenter stores large audio/video resources of a project in an external data folder named PROJECT_FILE_files. When copying, moving, or renaming a project file, please make sure to copy, move, or rename its data folder (if any) accordingly.
In case you rename the project, please take a look at this thread to find a solution:
Regards,